Natural resources such as gas, oil, and water in a subterranean formation are usually produced by drilling a well bore down to a subterranean formation while circulating a drilling fluid in the wellbore. Fluids used in drilling, completion, or servicing of a wellbore can be lost to the subterranean formation while circulating the fluids in the wellbore. In particular, the fluids may enter the subterranean formation via depleted zones, zones of relatively low pressure, loss circulation zones having naturally occurring fractures, weak zones having fracture gradients exceeded by the hydrostatic pressure of the drilling fluid, and so forth.
One of the contributing factors may be lack of precise information on the dimensions of loss circulation areas, which can range from microfractures to vugular zones. Depending on the extent of fluid volume losses, loss circulation is classified as seepage loss, moderate loss, or severe loss. For oil-based fluids, losses of 10-30 barrels per hour are considered moderate, and losses greater than 30 barrels per hour are considered severe. For water-based fluids, losses between 25 and 100 barrels are considered moderate, and losses greater than 100 barrels are considered severe. For severe losses, the dimensions of the loss circulation zones cannot be estimated which makes it difficult to design loss circulation treatment pills based on the sized particles. The revenue loss due to loss circulation materials (LCM) problems extends into tens of millions of dollars.
Loss circulation treatments involving various plugging materials have been used to prevent or lessen the loss of fluids from wellbores. The ideal loss circulation treatment solution will have to be adaptable to any dimension or shape of the loss circulation zone. Thus, there is a need for a composition that can form-fill upon placement, irrespective of the shape and size of the thief zone.